Actionable CV-19 Guide to Handling Packages and Deliveries
Usable Numbers on How to Handle Deliveries Safely
There are a bunch of articles online about package delivery handling, but all of the advice seems to be generalized and vague. This article is an attempt to give you quantitative risk info on how best to manage the risk of incoming deliveries based on the latest research (27 Mar 2020).
The safest situation is to have stockpiled all goods before the virus began spreading, so that you never have to receive any deliveries. Since you’re reading this, you didn’t do that (or you forgot something) and you have now ordered it delivered to your house. This implies that whatever you ordered is urgent, i.e. you have to open and use it “soon.” Thus, you are faced with a risk tradeoff between handling and opening a package and going without that item. This essay attempts to give you some quantitative risk numbers so you can balance the relative risks involved.
The advice given here is derived from the recent research published in the New England Journal of Medicine. The study has not been peer-reviewed (much like a lot of the quickly-executed research on COVID-19), but we will assume that the researchers involved are doing their best: I imagine that they also have a personal interest in the data they are reporting being accurate.
Key Ideas
Just because the virus “can still be detected” on a surface after X hours/days does not mean it is equally dangerous after those X hours have passed.
A lot of headlines reporting on this study took the form of “Coronoavirus Stays Stable On Surfaces For Hours.” This implies that the surface remains just as infectious 8 hours after coming into contact with infected droplets as it was at the beginning. This is not true.
The presence of infectious particles follows an exponential dropoff. This means that the half-life period is the most important figure in your personal risk management:
If the virus’s half-life on a certain surface is 8 hours, then after 8 hours there are roughly 50% as many virus particles as at the beginning. After another 8 hours, there are now 25% as many virus particles as at the beginning. This is key to understanding how likely you are to becoming infected by touching a virus-contaminated surface, and potentially how severe the infection will be for you.
Here Are the Real Usable Numbers
How long should you wait?
From the data in the study, surfaces can be roughly divided into two groups: copper and cardboard, and plastic and steel.
If your aim is to remain perfectly safe, you should wait 48 hours before touching any copper or cardboard, and 72 hours before touching any steel or plastic.
The amount of viable virus on those surfaces goes down by 3 orders of magnitude after those periods of time has passed.
That is, if you consider your risk of infection to be 100% if you were to immediately touch a cardboard package handed directly to you, waiting 48 hours means that your risk falls to 0.1%.
Your risk of infection probably doesn’t start at 100%, but that’s the worst-case and most conservative scenario.
What If I Need That Package Right Now?
In general, if you can wait a few hours, you dramatically decrease your risk of infection from a contaminated surface.
The half-life of the virus on a cardboard surface is about 5 hours. On steel it’s about 7 hours, and on plastic it’s 8 hours. (On copper, it’s 2 hours — but I don’t know anyone who’s receiving copper packages)
This means that if you receive a cardboard package and you let it sit for 5 hours, your risk of infection just got cut in half. Another 5 hours and it’s down to 25%.
This means that even if you received a plastic box that an infected delivery person coughed on directly just before they dropped it off, if you can wait a full day before opening it, your risk of infection is down to 12.5%. If it’s a cardboard box, waiting a full day brings it down to 3%.
This also means that contents inside a box or envelope that has traveled a day or two to reach you are unlikely to be contain infectious virus particles, even if the person who put them there was infected.
Again, if you can wait even longer, you can reduce your infection chances to near-zero. These numbers are intended to help you balance your risk against a situation where you need to open a package immediately or very soon.
The data from which I derived these rules of thumb are here:
Other Things You Can Do
The virus has a lipid (oil) envelope, which means it is likely to dissolve in soap.
This is one of the few lucky breaks we got in this pandemic — you don’t need harsh chemicals to kill this thing, just soap.
So another thing you can do is keep a container of soapy water, and if you don’t mind getting your packages a little wet and sticky, wipe the surfaces of the package with soapy water.
However, I have found no specific research verifying this thing about soap.
The earliest mention of it as relating to CV-19 is from this tweet by a Johns Hopkins scientist.
Technically speaking, there is no specific research on CV-19 as it relates to soap (or alcohol), but this is largely because it’s established disease-handling practice that washing hands with alcohol is useful, and that the structure of the virus is well-understood so the lipid envelope interaction with soap is plausible to the point that no one thinks doing an experiment on it is likely to yield a novel or surprising result.
You can also expose the package to UV-C light (not UVA or UVB), which is known to break down viruses.
However, I do not recommend this unless you have a dedicated sealed room for this and very careful eye-protection protocol.
UV-C light is extremely damaging to human tissue (especially your eyes), and in the end may cause more harm to you and your family members than the amount of harm you’d suffer from possible COVID-19 infection.
I am attempting to write a series of articles summarizing the best known science on COVID-19 and presenting it in a digestible and actionable format for non-technical people.
If you found this useful, here are some other pieces:
When can we lift the lockdown and restart our economy?
Free, Widespread Testing Is The Only Way America Goes Back To Normal
Should young people be concerned?
Up to 20% of Young People Who Get Coronavirus Could Still Die
How is this worse than the flu?
It’s The Rate of Hospitalizations, Stupid
Some details are elided for simplicity, and my goal is to give you a sense of agency in a complex and uncertain time:
This is what we know, and here’s what you should do to maximize our collective chance of success.
